Studies will be continued on the biosynthesis of membrane-bound nitrate reductase of Escherichia coli, and on the biosynthesis of the phage-directed major protein, protein 2, found on the surface of E. coli lysogenic for phage PA-2. In the latter case, the emphasis will be on identifying the structural gene for the protein, determining whether the protein is processed from a precursor, and identifying any post-translational modification involved in biosynthesis of the protein. A new project will be initiated to study complement-mediated cell killing employing specific antisera directed against the bacteriophage lambda receptor (lamB gene product) on the cell surface. This will be used to determine the number and arrangement of antigens on a bacterial cell surface required to mediate complement action.